Clamping device



Aug. 11, 11953 R. PETERS 2,648,240

CLAMPING DEVICE Filed May 5l, 1952 I INVENTOR. zo" I' uboLPH PETERS -L 4. 7 3p. Il .5 BY www@ 5o ATTORNEYS Patented Aug. 11, 1953 UNITED STATES PATENT OFFICE CLAMPING DEVICE Rudolph Peters, Oakland, Calif.

Application May 31, 1952, Serial No. 290,981

This invention relates to a clamping device for holding. an object on a drill press table during drilling operation.

It h-as been always a problem in a drilling operation to center a piece to be drilled under the drill and have it firmly secured to a drill press table. Usually a piece to be drilled is rst carefully centered under a drill, and thereafter the sameis securedto a drill press table by means of a lclamp or otherwise. Quite often securing a piece to a `drill press table moves the piece slightly,Y and thereupon it has to be centered again. These operation have to be carefully per- :formed andA take a lot of time and attention. If a -piece is not properly and sufficiently secured, it maymove and vbreak the drill, or it may become loose and start to spin with the drill which often causes accidents.

The vobject of vthis invention is to provide a device for holding `an object on a drill press table by which an object to be `drilled is automatically centered inrelation to the drill and locked by rotation of the latter to the drill press table.

Another object of this invention is to provide a device of the t-y-pe described which may be used on drill press tables of different size and which may accommodate objects of different sizes.

Still another object of this invention is to provide Ia device which is simple in construction, eiiicient for the -purpose intended, cheap to produce .and Operate- Other objects and advantages will appear as the specificationv proceeds and the novel features of therdevice will be particularly pointed out in theclaimsvhereto annexed.

In this specification and the annexed drawings, the invention is illustrated in the form considered to be the best but it is understood, that the invention is not limited to such form, and it is also to be understood that in and by the claims following the description, it is desired to cover the invention in whatsoever form it may be embodied.

My invention is illustrated in the accompanying drawing forming a part of the specification in which:

Fig. 1 is a plan view of the device shown as used on a drill press table and holding a vice.

Fig. 2 is a side view of the Fig. 1.

Fig. 3 is an enlarged end view of the device, some parts being shown in section, and

Fig. 4 is a cross-section of 'a modified form of the swivel.

In detail, my device, shown in Figs. 1-3, consists of a pair of hollow bars 2 extending beyond the 6 Claims. (Cl. 'T7-63) Cri length of a, drill press table 3. The latter usually consists of an elevated central portion Leurrounded by an oil groove 5 formed by an outer .lip 6 extending upwardly Iand around said central 'portion 4. The outer wall of the lip 6 slopes downwardly and inwardlyy at an angle to the central Verticalaxis of the table.

Each bar 2 has a. longislot 'I Aat the end `8 and round holes 9 at the end I0 thereof through which slots and one of the holes pass .swivels II and `I2 respectively. -Each swivel has a shank I3 passing through the slot 'l or the hole 9 inthe bar 2. The shank I3 carries on the top thereof a washer I5 and a retaining ring I6 which is inserted in a, groove Il. in said shank and lprevents the washer I5v from moving upwardly. A base 20 extends downwardly from said shank, which baseis of considerably larger diameter than that of said swivel, and has one side thereof facing the drill press table 3 leveled as shown vat 2|.

This arrangement permits each ofthe swivels `I-I and I2 to rotate freelyin said'slots or holes, and yet said swivels are securely locked against vertical movements in said bars.

The swivel II at the end fmay be moved in said slot 'I and held in a desired position `by a bolt -22 passing through a washer 23`=and a slot `2li adjoining said slot l. 'The bolt 22 terminates in a threaded khole 26 of a Ilink. 2,1. The latter has a hole28 through whichtheshank I3 passes. rIn order to adjust the position of saidswivel II, the bolt 22 is loosened 4and moved in theslot 24 thus ymoving the link 21 andthe swivel II into a'fdesired position. Thereupon the bolt-22 i-s tightened, which securely locks the swivel rI I in a new position.

yAdjustments `for greater distance betweenthe swivels II and A'I2 on the same lbar 2 are made by moving the swivel I2 near the end I0 from one hole 9 into another one.

The swivels II of each bar are connected by an adjusting rod 32, which passes through the base 20 of each swivel. The bars 2 and the rods 32 form a parallelogram in which the angular relation of the bars and rods may be easily changed. Each rod 32 is provided with a retaining ringr 33 on one end thereof and has its other end threaded as shown at 34 to admit a knurled adjusting nut 36.

The operation of the device is as follows: The device is placed on the drill press table 3 and the distance between the swivels II and I2 of each bar 2 is so adjusted as to be slightly bigger than the length of the table which permits said device to be moved freely forth and back on said table. An object to be drilled is placed into a usual hand vice 40 and locked therein by a screw 4|. The vice 40 is placed on the drill table 3 between the bars 2. The distance between the bars 2 is yso adjusted by the adjusting rods 32 as to be slightly bigger than the width of said vice which permits the vice to be moved freely between said bars. Then the the vice 40 is moved under the drill 43 to place the object under the same so that said drill is exactly above the center of the future hole. The drill is gradually pressed down. Rotation of the drill 43 forces the object, the vice and the device to rotate, which rotation is stopped when the bases 2|) come in contact with the outer walls of the lip 6, as shown in Figs. l and 2. The device now occupies a position in which the adjusting rods 32 are substantially parallel to the sides of the drill press table 3 and the bars 2 are at an angle to said sides, thus being closer to each other than when said bars 2 were at the right angle to said sides. This jams the vice 40 between the bars 2 with considerable force. The bases 20 abut said outer walls of the lip 6 by their leveled sides 2|, and thus securely press the device downwardly. Consequently, the rotation of the device at one and the same time locks the vice in the device and the latter to the drill press table. The vice 40 centers itself automatically -as at the beginning of the rotation as the vice is free to move on table in any direction.

It is obvious that an object to be drilled may be-placed directly between the bars 2, if said object is of such shape as it may be clamped securely between the straight parallel sides of the bars 2.

Fig. 4 shows a modied form of the base 20, in which a disk 50 with a sharp edge is rotatably attached to the bottom thereof. This arrangement may be used with a drill press table in which the outer wall 5| is vertical. The rotation of the device forces the disks 50 to bite into the wall 5| and thus prevent the device from moving upwardly.

I claim:

1. A device for holding an object to be drilled on a. drill press table comprising a pair of parallel bars, a pair of rods connecting said bars, swivel means connecting said rods with said bars permitting the latter to swing in relation to said rods, ysaid swivel means having extensions for engaging the side of said drill press table.

2. A device for holding an object to be drilled on a drill press table, comprising a pair of parallel bars adapted to retain an object therebetween, a swivel mounted at each end of said bars, a, pair of rods, each of said rods being operatively connected to the swivels of the adjacent ends of said bars, each of the swivels having a part dependent therefrom for engaging the side of said drill press table.

3. A device for holding an object to be drilled by a drill press on a drill press table, comprising a pair of parallel bars, a pair of parallel rods connecting said bars at their respective ends to form a parallelogram, a pivot means connecting each bar and rod permitting said bars and rods to assume various angular positions in relation to each other and to jam between said bars an object to be drilled; said pivot means extending beyond said bars to engage the side of said drill press table, when said device is on said table.

4. The combination of a drill press table with a device for holding an object to be drilled said device comprising a pair of bars resting on the table, swivel means at each end of said bars, a pair of rods, each rod operatively connecting the swivel means of the adjacent ends of said bars, said swivel means having means for engaging the side of the drill press table when said device is rotated thereon.

5. The combination of a drill press table with a device for holding an object to be drilled, said device comprising a pair of parallel bars, a pair of parallel rods connecting the ends of said bars and forming with said bars a parallelogram; pivot means for connecting said bars and rods, said pivot means permitting said bars and rods to assume various angular positions in relation to each other and to jam the object between said bars, said pivot means extending downwardly beyond the upper surface of the drill press table and adapted to engage the side thereof to hold the device downwardly.

6. The combination of a drill press table with a device for holding an object to be drilled, said device comprising a pair of bars resting on the table, swivel means at each end o1' said bars, a pair of rods, each rod operatively connecting the swivel means of the adjacent ends of said bars, said swivel means having means for engaging the side of the drill press table when ysaid device is rotated thereon, and means for adjusting the distances between said bars and said rods.

RUDOLPH PETERS.

References Cited in the le of this patent UNITED STATES PATENTS Number 

